The effects of poststroke aerobic exercise on neuroplasticity: a systematic review of animal and clinical studies

Measurement properties of activity monitoring for a rehabilitation (AMoR) platform in post-stroke individuals in a simulated home environment

AIM

The aim of this study was to evaluate the measurement properties of activity monitoring for a rehabilitation (AMoR) platform for step counting, time spent in sedentary behavior, and postural changes during activities of daily living (ADLs) in a simulated home environment.

METHODS

Twenty-one individuals in the post-stroke chronic phase used the AMoR platform during an ADL protocol and were monitored by a video camera. Spearman's correlation coefficient, mean absolute percent error (MAPE), intraclass correlation coefficient (ICC), and Bland-Altman plot analyses were used to estimate the validity and reliability between the AMoR platform and the video for step counting, time spent sitting/lying, and postural changes from sit-to-stand (SI-ST) and sit-to-stand (ST-SI).

RESULTS

Validity of the platform was observed with very high correlation values for step counting (rs = 0.998) and time spent sitting/lying (rs = 0.992) and high correlation for postural change of SI-ST (rs = 0.850) and ST-SI (rs = 0.851) when compared to the video. An error percentage above 5% was observed only for the SI-ST postural change (7.13%). The ICC values show excellent agreement for step counting (ICC3, k = 0.999) and time spent sitting/lying (ICC3, k = 0.992), and good agreement for SI-ST (ICC3, k = 0.859) and ST-SI (ICC3, k = 0.936) postural change. Values of the differences for step counting, sitting/lying time, and postural change were within the limits of agreement according to the analysis of the Bland-Altman graph.

CONCLUSION

The AMoR platform presented validity and reliability for step counting, time spent sitting/lying, and identification of SI-ST and ST-SI postural changes during tests in a simulated environment in post-stroke individuals.

Effects of exercise on post-stroke cognitive function: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

A growing body of research examining the effect of exercise on cognitive function in stroke patients, while findings of available studies were conflicting.

OBJECTIVES

We aimed to estimate the effect of exercise on cognitive function in stroke patients.

METHODS

For this systematic review and meta-analysis, we searched PubMed, Web of Science, Embase, Cochrane, and Scopus electronic databases, through 13 March 2023. The three-level restricted maximum likelihood random effects model was used to synthesize the data.

RESULTS

Twenty-five studies met the inclusion criteria. There was a significant effect of exercise on improving cognitive function in stroke patients (Cohen's d = 0.37, 95% CI, 0.16 to 0.58, p < 0.01, I2  = 22.12%). Subgroup analysis showed that exercise significantly improved memory. In addition, aerobic exercise, exercise conducted 12 weeks or more, 3 times or more per week, less than 60 minutes per session, less than 180 minutes per week, and up to 12 months post-stroke increased cognitive function significantly.

CONCLUSIONS

Exercise improved cognitive function in stroke patients. To improve cognitive function, this meta-analysis provides clinicians with evidence to recommend that stroke patients participate in aerobic exercise at least 3 times per week for 30-60 minutes, with a goal of 180 minutes per week being achieved by increasing the frequency of exercise. Exercise initiated within 12 months post-stroke and continued for 12 weeks or more is most beneficial for improving cognitive function.

Top-Down and Bottom-Up Mechanisms of Motor Recovery Poststroke

Stroke remains a leading cause of disability. Motor recovery requires the interaction of top-down and bottom-up mechanisms, which reinforce each other. Injury to the brain initiates a biphasic neuroimmune process, which opens a window for spontaneous recovery during which the brain is particularly sensitive to activity. Physical activity during this sensitive period can lead to rapid recovery by potentiating anti-inflammatory and neuroplastic processes. On the other hand, lack of physical activity can lead to early closure of the sensitive period and downstream changes in muscles, such as sarcopenia, muscle stiffness, and reduced cardiovascular capacity, and blood flow that impede recovery.

Intensive Aerobic Cycling Is Feasible and Elicits Improvements in Gait Velocity in Individuals With Multiple Sclerosis: A Preliminary Study

BACKGROUND

Aerobic exercise (AEx) has many potential benefits; however, it is unknown whether individuals with multiple sclerosis (MS) can attain the optimal intensity and duration to harness its effects. Forced-rate exercise (FE) is a novel paradigm in which the voluntary pedaling rate during cycling is supplemented to achieve a higher exercise intensity. The aim of this pilot trial was to investigate the feasibility and initial efficacy of a 12-week FE or voluntary exercise (VE) cycling intervention for individuals with MS.

METHODS

Twenty-two participants with MS (Expanded Disability Severity Scale [EDSS] 2.0-6.5) were randomly assigned to FE (n = 12) or VE (n = 10), each with twice weekly 45-minute sessions at a prescribed intensity of 60% to 80% of maximum heart rate (HR).

RESULTS

Eighteen individuals (FE = 11; VE = 7) completed the intervention, however, adaptations were required in both groups to overcome barriers to cycling. Overall, participants exercised for an average of 42.2 ± 2.3 minutes at an aerobic intensity of 65% ± 7% of maximum HR and a pedaling cadence of 67.3 ± 13.3 RPM. Cycling led to improved treadmill walking speed (0.61 to 0.68 m/sec, P = .010), with somewhat greater improvement with FE compared to VE (increase of 0.09 vs 0.03 m/s, respectively, P = .17) post intervention. Notably, the participant with the highest disability level (EDSS 6.5) tolerated FE but not VE.

CONCLUSIONS

Aerobic exercise is feasible for individuals with MS, although those with increased disability may require novel paradigms such as FE to achieve targeted intensity. Further trials are warranted to investigate the effects of FE across the MS disability spectrum.

The Utilization of Forced-Rate Cycling to Facilitate Motor Recovery Following Stroke: A Randomized Clinical Trial

BACKGROUND

The potential for aerobic exercise (AE) to enhance neuroplasticity post-stroke has been theorized but not systematically investigated. Our aim was to determine the effects of forced-rate AE (FE) paired with upper extremity (UE) repetitive task practice (FE + RTP) compared to time-matched UE RTP (RTP only) on motor recovery.

METHODS

A single center randomized clinical trial was conducted from April 2019 to December 2022. Sixty individuals ≥6 months post-stroke with UE hemiparesis were randomized to FE + RTP (N = 30) or RTP only (N = 30), completing 90-minute sessions, 3×/week for 8 weeks. The FE + RTP group underwent 45-minute of FE (5-minute warm-up, 35-minute main set, and 5-minute cool down) followed by 45-minute of UE RTP. The RTP only group completed 90-minute of RTP. Primary outcomes were the Fugl-Meyer Assessment (FMA) and Action Research Arm Test (ARAT). The 6-minute Walk Test (6MWT, secondary outcome) assessed walking capacity.

RESULTS

Sixty individuals enrolled and 56 completed the study. The RTP only group completed more RTP in terms of repetitions (411.8 ± 44.4 vs 222.8 ± 28.4, P < .001) and time (72.7 ± 6.7 vs 37.8 ± 2.4 minutes, P < .001) versus FE + RTP. There was no significant difference between groups on the FMA (FE + RTP, 36.2 ± 10.1-44.0 ± 11.8 and RTP only, 34.4 ± 11.0-41.2 ± 13.4, P = .43) or ARAT (FE + RTP, 32.5 ± 16.6-37.7 ± 17.9 and RTP only, 32.8 ± 18.6-36.4 ± 18.5, P = .88). The FE + RTP group demonstrated greater improvements on the 6MWT (274.9 ± 122.0-327.1 ± 141.2 m) versus RTP only (285.5 ± 160.3-316.9 ± 170.0, P = .003).

CONCLUSIONS

There was no significant difference between groups in the primary outcomes. The FE + RTP improved more on the 6MWT, a secondary outcome.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03819764.

The effects of kinesiophobia, fatigue, and quality of life on physical activity in patients with stroke

BACKGROUND

Physical activity decreases after stroke due to various factors and the causes and effects of these factors remain unclear.

OBJECTIVES

This study aimed todetermine the effects of kinesiophobia, fatigue, and quality of life on physical activity in patients with stroke.

METHODS

The study included 32 patients (13 females/19 males), all evaluated using the Stroke Rehabilitation Assessment of Movement, Barthel Index, Tampa Kinesiophobia Scale-fatigue, Fatigue Impact Scale and Stroke-Specific Quality of Life Scale. The SenseWear multisensory activity monitor was worn on the arm of the patients for 1 week to evaluate active energy expenditure, step count, and rest periods in relation to physical activity. Multiple linear regression analysis was used to examine the effects of the independent variables kinesiophobia, fatigue, and quality of life on the dependent variables of active energy expenditure, step count, and rest periods.

RESULTS

The mean age of the patients was 52.31 ± 14.76 years. According to the multiple regression analysis results, kinesiophobia (p = 0.011) and quality of life (p = 0.009) are significant determinants of active energy expenditure and quality of life (p = 0.001) is a significant determinant of the step count in patients with stroke. Kinesiophobia, fatigue, and quality of life were not determinants of rest periods (p > 0.05).

CONCLUSIONS

The study results showed that kinesiophobia and quality of life are important determinants of physical activity in patients with stroke. Combined evaluation in the clinic of motor findings and non-motor factors, which are often ignored, and the application of target-oriented approaches to these problems will make a significant contribution to the success of stroke rehabilitation.

A roadmap for research in post-stroke fatigue: Consensus-based core recommendations from the third Stroke Recovery and Rehabilitation Roundtable

RATIONALE

Fatigue affects almost half of all people living with stroke. Stroke survivors rank understanding fatigue and how to reduce it as one of the highest research priorities.

METHODS

We convened an interdisciplinary, international group of clinical and pre-clinical researchers and lived experience experts. We identified four priority areas: (1) best measurement tools for research, (2) clinical identification of fatigue and potentially modifiable causes, (3) promising interventions and recommendations for future trials, and (4) possible biological mechanisms of fatigue. Cross-cutting themes were aphasia and the voice of people with lived experience. Working parties were formed and structured consensus building processes were followed.

RESULTS

We present 20 recommendations covering outcome measures for research, development, and testing of new interventions and priority areas for future research on the biology of post-stroke fatigue. We developed and recommend the use of the Stroke Fatigue Clinical Assessment Tool.

CONCLUSIONS

By synthesizing current knowledge in post-stroke fatigue across clinical and pre-clinical fields, our work provides a roadmap for future research into post-stroke fatigue.

Measuring Neuroplasticity in Response to Cardiovascular Exercise in People With Stroke: A Critical Perspective

BACKGROUND

Rehabilitative treatments that promote neuroplasticity are believed to improve recovery after stroke. Animal studies have shown that cardiovascular exercise (CE) promotes neuroplasticity but the effects of this intervention on the human brain and its implications for the functional recovery of patients remain unclear. The use of biomarkers has enabled the assessment of cellular and molecular events that occur in the central nervous system after brain injury. Some of these biomarkers have proven to be particularly valuable for the diagnosis of severity, prognosis of recovery, as well as for measuring the neuroplastic response to different treatments after stroke.

OBJECTIVES

To provide a critical analysis on the current evidence supporting the use of neurophysiological, neuroimaging, and blood biomarkers to assess the neuroplastic response to CE in individuals poststroke.

RESULTS

Most biomarkers used are responsive to the effects of acute and chronic CE interventions, but the response appears to be variable and is not consistently associated with functional improvements. Small sample sizes, methodological variability, incomplete information regarding patient's characteristics, inadequate standardization of training parameters, and lack of reporting of associations with functional outcomes preclude the quantification of the neuroplastic effects of CE poststroke using biomarkers.

CONCLUSION

Consensus on the optimal biomarkers to monitor the neuroplastic response to CE is currently lacking. By addressing critical methodological issues, future studies could advance our understanding of the use of biomarkers to measure the impact of CE on neuroplasticity and functional recovery in patients with stroke.

Mechanisms of Post-Stroke Fatigue: A Follow-Up From the Third Stroke Recovery and Rehabilitation Roundtable

BACKGROUND

Post-stroke fatigue (PSF) is a significant and highly prevalent symptom, whose mechanisms are poorly understood. The third Stroke Recovery and Rehabilitation Roundtable paper on PSF focussed primarily on defining and measuring PSF while mechanisms were briefly discussed. This companion paper to the main paper is aimed at elaborating possible mechanisms of PSF.

METHODS

This paper reviews the available evidence that potentially explains the pathophysiology of PSF and draws parallels from fatigue literature in other conditions. We start by proposing a case for phenotyping PSF based on structural, functional, and behavioral characteristics of PSF. This is followed by discussion of a potentially significant role of early inflammation in the development of fatigue, specifically the impact of low-grade inflammation and its long-term systemic effects resulting in PSF. Of the many neurotransmitter systems in the brain, the dopaminergic systems have the most evidence for a role in PSF, along with a role in sensorimotor processing. Sensorimotor neural network dynamics are compromised as highlighted by evidence from both neurostimulation and neuromodulation studies. The double-edged sword effect of exercise on PSF provides further insight into how PSF might emerge and the importance of carefully titrating interventional paradigms.

CONCLUSION

The paper concludes by synthesizing the presented evidence into a unifying model of fatigue which distinguishes between factors that pre-dispose, precipitate, and perpetuate PSF. This framework will help guide new research into the biological mechanisms of PSF which is a necessary prerequisite for developing treatments to mitigate the debilitating effects of post-stroke fatigue.

A roadmap for research in post-stroke fatigue: Consensus-based core recommendations from the third Stroke Recovery and Rehabilitation Roundtable

RATIONALE

Fatigue affects almost half of all people living with stroke. Stroke survivors rank understanding fatigue and how to reduce it as one of the highest research priorities.

METHODS

We convened an interdisciplinary, international group of clinical and pre-clinical researchers and lived experience experts. We identified four priority areas: (1) best measurement tools for research, (2) clinical identification of fatigue and potentially modifiable causes, (3) promising interventions and recommendations for future trials, and (4) possible biological mechanisms of fatigue. Cross-cutting themes were aphasia and the voice of people with lived experience. Working parties were formed and structured consensus building processes were followed.

RESULTS

We present 20 recommendations covering outcome measures for research, development, and testing of new interventions and priority areas for future research on the biology of post-stroke fatigue. We developed and recommend the use of the Stroke Fatigue Clinical Assessment Tool.

CONCLUSIONS

By synthesizing current knowledge in post-stroke fatigue across clinical and pre-clinical fields, our work provides a roadmap for future research into post-stroke fatigue.

Motor Rehabilitation Provides Modest Functional Benefits After Intracerebral Hemorrhage: a Systematic Review and Meta-Analysis of Translational Rehabilitation Studies

Few certainties exist regarding the optimal type, timing, or dosage of rehabilitation after stroke. Despite differing injury mechanisms and recovery patterns following ischemic and hemorrhagic stroke, most translational stroke research is conducted after ischemia. As we enter the era of personalized medicine, exploring subtype-specific treatment efficacy is essential to optimizing recovery. Our objective was to characterize common rehabilitation interventions used after in vivo preclinical intracerebral hemorrhage (ICH) and assess the impact of post-ICH rehabilitation (vs. no-rehabilitation) on recovery of motor function. Following PRISMA guidelines, a systematic review (Academic Search Complete, CINAHL, EMBASE, Medline, PubMed Central) identified eligible articles published up to December 2022. Risk of bias (SYRCLE) and study quality (CAMARADES) were evaluated, and random-effects meta-analysis was used to assess treatment efficacy in recovery of forelimb and locomotor functions. Thirty articles met inclusion criteria, and 48 rehabilitation intervention groups were identified. Most used collagenase to model striatal ICH in young, male rodents. Aerobic exercise, enriched rehabilitation, and constraint-induced movement therapy represented ~ 70% of interventions. Study quality was low (median 4/10, range 2-8), and risk of bias was unclear. Rehabilitation provided modest benefits in skilled reaching, spontaneous impaired forelimb use, and locomotor function; however, effects varied substantially by endpoint, treatment type, and study quality. Rehabilitation statistically improves motor function after preclinical ICH, but whether these effects are functionally meaningful is unclear. Incomplete reporting and variable research quality hinder our capacity to analyze and interpret how treatment factors influence rehabilitation efficacy and recovery after ICH.

Moderate intensity aerobic exercise may enhance neuroplasticity of the contralesional hemisphere after stroke: a randomised controlled study

Upregulation of neuroplasticity might help maximize stroke recovery. One intervention that appears worthy of investigation is aerobic exercise. This study aimed to determine whether a single bout of moderate intensity aerobic exercise can enhance neuroplasticity in people with stroke. Participants were randomly assigned (1:1) to a 20-min moderate intensity exercise intervention or remained sedentary (control). Transcranial magnetic stimulation measured corticospinal excitability of the contralesional hemisphere by recording motor evoked potentials (MEPs). Intermittent Theta Burst Stimulation (iTBS) was used to repetitively activate synapses in the contralesional primary motor cortex, initiating the early stages of neuroplasticity and increasing excitability. It was surmised that if exercise increased neuroplasticity, there would be a greater facilitation of MEPs following iTBS. Thirty-three people with stroke participated in this study (aged 63.87 ± 10.30 years, 20 male, 6.13 ± 4.33 years since stroke). There was an interaction between Time*Group on MEP amplitudes (P = 0.009). Participants allocated to aerobic exercise had a stronger increase in MEP amplitude following iTBS. A non-significant trend indicated time since stroke might moderate this interaction (P = 0.055). Exploratory analysis suggested participants who were 2-7.5 years post stroke had a strong MEP facilitation following iTBS (P < 0.001). There was no effect of age, sex, resting motor threshold, self-reported physical activity levels, lesion volume or weighted lesion load (all P > 0.208). Moderate intensity cycling may enhance neuroplasticity in people with stroke. This therapy adjuvant could provide opportunities to maximize stroke recovery.

Physical Activity Trajectories and Functional Recovery After Acute Stroke Among Adults in Sweden

Importance

The optimum level and timing of poststroke physical activity interventions to enhance functional recovery remain unclear.

Objective

To assess the level of physical activity in the first 6 months after stroke among individuals with similar physical activity patterns over time and to investigate the association between physical activity trajectories and functional recovery at 6 months after stroke.

Design, Setting, and Participants

This cohort study obtained data from the Efficacy of Fluoxetine-a Randomized Controlled Trial in Stroke, which was conducted in 35 stroke and rehabilitation centers across Sweden from October 2014 to June 2019. Adult participants (aged >18 years) were recruited between 2 and 15 days after stroke onset and followed up for 6 months. Participants who withdrew or were lost to follow-up were excluded from the longitudinal analysis. Data analyses were performed between August 15 and October 28, 2022.

Exposures

Physical activity was assessed at 1 week, 1 month, 3 months, and 6 months. Multiple factors associated with physical activity trajectories were investigated. Association of the distinct trajectories with functional recovery was assessed in multivariable logistic regression.

Main Outcomes and Measures

The primary outcomes were the distinct physical activity trajectories over time, which were identified using group-based trajectory modeling. The secondary outcome was the functional recovery at 6 months after stroke, which was assessed using the modified Rankin Scale.

Results

Of the 1367 included participants (median [IQR] age, 72 years [65-79] years; 844 males [62%]), 2 distinct trajectory groups were identified: increaser (n = 720 [53%]) and decreaser (647 [47%]). The increaser group demonstrated a significant increase in physical activity level (mean difference, 0.27; linear slope β1 = 0.46; P < .001) and sustained it at light intensity from 1 week to 6 months, whereas the decreaser group showed a decline in physical activity and eventually became inactive (mean difference, -0.26; linear slope β1 = 1.81; P < .001). Male participants and those with normal cognition had higher odds of being in the increaser group, regardless of stroke severity. Increasing physical activity and sustaining it at light intensity were associated with a good functional outcome at 6 months (adjusted odds ratio, 2.54; 99% CI, 1.72-3.75; P < .001).

Conclusions ad Relevance

Results of this study suggest that increased physical activity was associated with functional recovery 6 months after stroke. Interventions targeting individuals with decreasing physical activity in the subacute phase of stroke may play a role in improved functional outcomes.

Association between exercise habit changes and incident dementia after ischemic stroke

We aimed to investigate the effects of exercise habit changes on the risk of incident dementia after ischemic stroke using the Korean National Health Insurance Services Database. This study included 223,426 patients with a new diagnosis of ischemic stroke between 2010 and 2016 who underwent two serial ambulatory health checkups. The participants were divided into four categories according to their habit change or regular exercise: persistent non-exercisers, new exercisers, exercise dropouts, and exercise maintainers. The primary outcome was new diagnosis of dementia. Multivariate Cox proportional models were used to assess the effects of changes in exercise habits on the risk of incident dementia. After a median of 4.02 years of follow-up, 22,554 (10.09%) dementia cases were observed. After adjusting for covariates, exercise dropouts, new exercisers, and exercise maintainers were significantly associated with a lower risk of incident dementia than persistent non-exercisers (adjusted hazard ratio [aHR] 0.937; 95% confidence interval [CI] 0.905-0.970, aHR 0.876; 95% CI 0.843-0.909, aHR 0.705; 95% CI 0.677-0.734, respectively). The impact of changes in exercise habit was more prominent in the 40-65 years age group. An energy expenditure ≥ 1000 metabolic equivalents of task-min/wk post-stroke, regardless of pre-stroke physical activity status, was mostly associated with a lower risk of each outcome. In this retrospective cohort study, initiating or continuing moderate-to-vigorous exercise after ischemic stroke was associated with a lower risk of dementia development. Further, pre-stroke regular physical activity also reduced the risk of incident dementia. The promotion of exercise in ambulatory stroke patients may reduce their future risk of incident dementia.

Translingual neurostimulation combined with physical therapy to improve walking and balance in multiple sclerosis (NeuroMSTraLS): Study protocol for a randomized controlled trial

INTRODUCTION

Physical rehabilitation restores lost function and promotes brain plasticity in people with Multiple Sclerosis (MS). Research groups worldwide are testing the therapeutic effects of combining non-invasive neuromodulation with physical therapy (PT) to further improve functional outcomes in neurological disorders but with mixed results. Whether such devices enhance function is not clear. We present the rationale and study design for a randomized controlled trial evaluating if there is additional benefit to the synergistic pairing of translingual neurostimulation (TLNS) with PT to improve walking and balance in MS.

METHODS AND ANALYSIS

A parallel group [PT + TLNS or PT + Sham], quadruple-blinded, randomized controlled trial. Participants (N = 52) with gait and balance deficits due to relapsing-remitting or progressive MS, who are between 18 and 70 years of age, will be recruited through patient registries in Newfoundland & Labrador and Saskatchewan, Canada. All participants will receive 14 weeks of PT while wearing either a TLNS or sham device. Dynamic Gait Index is the primary outcome. Secondary outcomes include fast walking speed, subjective ratings of fatigue, MS impact, and quality of life. Outcomes are assessed at baseline (Pre), after 14 weeks of therapy (Post), and 26 weeks (Follow Up). We employ multiple methods to ensure treatment fidelity including activity and device use monitoring. Primary and secondary outcomes will be analyzed using linear mixed-effect models. We will control for baseline score and site to test the effects of Time (Post vs. Follow-Up), Group and the Group x Time interaction as fixed effects. A random intercept of participant will account for the repeated measures in the Time variable. Participants must complete the Post testing to be included in the analysis.

ETHICS AND DISSEMINATION

The Human Research Ethics Boards in Newfoundland & Labrador (HREB#2021.085) & Saskatchewan (HREB Bio 2578) approved the protocol. Dissemination avenues include peer-reviewed journals, conferences and patient-oriented communications.

Effects of moderate-intensity aerobic exercise on serum BDNF and motor learning in the upper-limb in patients after chronic-stroke: A randomized, controlled feasibility study with embedded health economic evaluation

BACKGROUND

Brain-derived neurotrophic factor (BDNF) promotes activity-dependent neuroplasticity and is released following aerobic-exercise.

OBJECTIVE

Feasibility and efficacy of 1.Moderate-Intensity Cycle-Ergometer-Training (MI-ET) and 2.Low-Intensity Circuit-Training (LI-CT) on BDNF-serum-concentration in chronic-stroke and consequently efficacy of motor-learning in varying BDNF-concentrations (neuroplasticity being the substrate for motor-learning) via upper-limb robotic-training (RT) in both groups.

METHODS

Randomised-control feasibility-study. 12-week, 3x/week intervention, 17 chronic-stroke-survivors randomized into: (1) MI-ET&RT or (2) LI-CT&RT. Both groups completed 40 mins MI-ET or LI-CT followed by 40 mins RT. Feasibility outcomes: (1) screening and enrollment-rates, (2) retention-rates, (3) adherence: (i) attendance-rates, (ii) training-duration, (4) adverse events. Primary clinical outcomes: 1. serum-BDNF changes pre-post training (immediate) and pre-training basal-levels over 12-weeks (long-term). 2.upper-limb performance with Action-Research-Arm-Test (ARAT). Additionally, feasibility of an embedded health economic evaluation (HEE) to evaluate health-costs and cost-effectiveness.

OUTCOMES

cost-questionnaire return-rates, cost-of-illness (COI) and Health-Utitility-Index (HUI).

RESULTS

21.5% of eligible and contactable enrolled. 10 randomized to MI-ET and 7 to LI-CT. 85% of training-sessions were completed in MI-ET (306/360) and 76.3% in LI-CT-group (165/216). 12-weeks: Drop-outs MI-ET-10%, LI-CT-43%.

CLINICAL OUTCOMES

No significant changes in immediate or long-term serum-BDNF in either group. Moderate-intensity aerobic-training did not increase serum-BDNF post-stroke. Individual but no group clinically-relevant changes in ARAT-scores. HEE outcomes at 12-weeks: 100% cost-questionnaires returned. Group-costs baseline and after treatment, consistently favouring MI-ET group. COI: (1-year-time-frame): MI-ET 67382 SD (43107) Swiss-Francs and LI-CT 95701(29473) Swiss-Francs.

CONCLUSION

The study is feasible with modifications. Future studies should compare high-intensity versus moderate-intensity aerobic-exercise combined with higher dosage arm-training.

Stimulation of functional recovery via neurorepair mechanisms by the traditional Japanese Kampo medicine, Ninjin'yoeito, and physical exercise in a rat ischemic stroke model

ETHNOPHARMACOLOGICAL RELEVANCE

Ninjin'yoeito (NYT), a traditional Japanese Kampo medicine consisting of 12 herbs, has been reported to improve cognitive dysfunction, depression, and neurological recovery in patients with neurovascular diseases such as Alzheimer's disease and stroke. Several studies have reported that the NYT components exert neurotrophic, neurogenic, and neuroprotective effects. In addition, exercise enhances neuroprotection and functional recovery after stroke. Rehabilitative exercises and pharmacological agents induce neurophysiological plasticity, leading to functional recovery in stroke patients. These reports indicate that NYT treatment and exercise may promote functional recovery following stroke through their beneficial effects. However, no study has determined the effects of NYT and the possible mechanisms of neurorepair and functional recovery after stroke.

AIM OF THE STUDY

This study aimed to investigate the combined effects of NYT and exercise on neuroprotection and functional recovery and the underlying mechanisms in a rat ischemic stroke model.

MATERIALS AND METHODS

Stroke was induced with 60-min middle cerebral artery occlusion (MCAO) followed by reperfusion in adult male Sprague-Dawley rats. After stroke, the rats were assigned to four groups: ischemia reperfusion (IR), NYT, exercise (Ex), and NYT + Ex. NYT-treated rats were fed a diet containing 1% NYT one day after stroke. Exercise was performed using a motorized treadmill for 5 days a week (8-15 m/min, 20 min/day), starting 3 days after stroke. The NYT treatment and exercise were continued for 4 weeks after the stroke. Infarct volume, neurological deficits, sensorimotor functions, expression of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase A (TrkA) and B (TrkB), caspase-3 activity, and the p-Akt/Akt ratio were examined by immunohistochemistry and western blotting.

RESULTS

Compared to the IR group, all treated groups indicated reduced infarct volumes. The NYT + Ex group showed significantly improved waking time and beam walking score compared with the IR group. The expression of NGF/TrkA/p-TrkA and BDNF/TrkB was significantly increased in the NYT + Ex group compared with those in the IR group, whereas the number of caspase-3 positive cells around the lesion was significantly lower in the NYT + Ex group than in the IR group. In addition, the ratio of p-Akt/Akt was significantly higher in the NYT + Ex group than in the IR group.

CONCLUSIONS

This study suggests that NYT in combination with exercise provides neuroprotective effects and improves sensorimotor function by stimulating NGF/TrkA and BDNF/TrkB, and by activating the Akt pathway in ischemic stroke of rats. NYT may be an effective adjunctive agent in post-stroke rehabilitation.

Test-Retest Reliability and Agreement of Single Pulse Transcranial Magnetic Stimulation (TMS) for Measuring Activity in Motor Cortex in Patients With Acute Ischemic Stroke

Background

Transcranial magnetic stimulation (TMS) is often used to examine neurophysiology. We aimed to investigate the inter-rater reliability and agreement of single pulse TMS in hospitalised acute ischemic stroke patients.

Methods

Thirty-one patients with first-time acute ischemic stroke (median age 72 (IQR 64-75), 35% females) underwent TMS motor threshold (MT) assessment in 4 muscles bilaterally, conducted by 1 of 2 physiotherapists. Test-retest reliability was evaluated using a two-way random effects model (2,1) absolute agreement-type Interclass Correlation Coefficient (ICC). Standard Error of Measurement (SEM) and Smallest Detectable Change (SDC) were used to evaluate agreement.

Results

Reliability, SEM, and SDC of TMS was found to be moderate in right opponens pollicis (0.78 [CI 95% 0.55-0.89], SEM: 4.51, SDC: 12.51), good in right vastus medialis and tibial anterior (0.88 [CI 95% 0.72-0.96], SEM: 2.89, SDC: 8.01 and 0.88 [CI 95% 0.76-0.94], SEM: 2.88, SDC: 7.98 respectively), and excellent in right and left biceps brachii (0.98 [CI 95% 0.96-0.99], SEM: 1.79 SDC: 4.96, and 0.94 [CI 95% 0.89-0.97], SEM: 2.17 SDC: 6.01), opponens pollicis (0.92 [CI 95% 0.83-0.96], SEM: 2.68 SDC: 8.26, vastus medialis (0.92 [CI 95% 0.84-0.96], SEM: 2.87 SDC: 7.95), and tibial anterior (0.93 [CI 95% 0.86-0.96], SEM: 2.51 SDC: 6.95).

Conclusion

The TMS demonstrated moderate to excellent inter-rater reliability confirming the ability of these measures to reliably discriminate between individuals in the current study sample. Improvements of less than 4.96 to 12.51 could be a result of measurement error and may therefore not be considered a true change.

The impact of aerobic and resistance training intensity on markers of neuroplasticity in health and disease

OBJECTIVE

To determine the effects of low- vs. high-intensity aerobic and resistance training on motor and cognitive function, brain activation, brain structure, and neurochemical markers of neuroplasticity and the association thereof in healthy young and older adults and in patients with multiple sclerosis, Parkinson's disease, and stroke.

DESIGN

Systematic review and robust variance estimation meta-analysis with meta-regression.

DATA SOURCES

Systematic search of MEDLINE, Web of Science, and CINAHL databases.

RESULTS

Fifty studies with 60 intervention arms and 2283 in-analyses participants were included. Due to the low number of studies, the three patient groups were combined and analyzed as a single group. Overall, low- (g=0.19, p = 0.024) and high-intensity exercise (g=0.40, p = 0.001) improved neuroplasticity. Exercise intensity scaled with neuroplasticity only in healthy young adults but not in healthy older adults or patient groups. Exercise-induced improvements in neuroplasticity were associated with changes in motor but not cognitive outcomes.

CONCLUSION

Exercise intensity is an important variable to dose and individualize the exercise stimulus for healthy young individuals but not necessarily for healthy older adults and neurological patients. This conclusion warrants caution because studies are needed that directly compare the effects of low- vs. high-intensity exercise on neuroplasticity to determine if such changes are mechanistically and incrementally linked to improved cognition and motor function.

Research Summit V: Optimizing Transitions From Infancy to Early Adulthood in Children With Neuromotor Conditions

PURPOSE

The purpose of this executive summary is to review the process and outcomes of the Academy of Pediatric Physical Therapy Research Summit V, "Optimizing transitions from infancy to young adulthood in children with neuromotor disabilities: biological and environmental factors to support functional independence."

SUMMARY OF KEY POINTS

An interdisciplinary group of researchers, representatives from funding agencies, and individuals with neuromotor disabilities and their parents participated in an intensive 2.5-day summit to determine research priorities to optimize life transitions for children with neuromotor disabilities. Recommended priorities for research included (1) promoting self-determination and self-efficacy of individuals with neuromotor disabilities and their families, (2) best care at the right time: evidence-based best practice care, led and navigated by families seamlessly across the lifespan, (3) strengthening connections between developmental domains to enhance function and participation, and (4) optimal dosing and timing to support adaptive bone, muscle, and brain plasticity across the lifespan.

The Effect of Endurance Training on Serum BDNF Levels in the Chronic Post-Stroke Phase: Current Evidence and Qualitative Systematic Review

Research in modern neurorehabilitation focusses on cognitive and motor recovery programmes tailored to each stroke patient, with particular emphasis on physiological parameters. The objectives of this review were to determine whether a single bout of endurance activity or long-term endurance activity regulates exercise-dependent serum brain-derived neurotrophic factor (BDNF) levels and to evaluate the methodological quality of the studies. To assess the effectiveness of endurance exercise among patients in the chronic post-stroke phase, a systematic review was performed, including searching EBSCOhost, PEDro, PubMed, and Scopus for articles published up to the end of October 2021. The PRISMA 2020 outline was used, and this review was registered on PROSPERO. Of the 180 papers identified, seven intervention studies (comprising 200 patients) met the inclusion criteria. The methodological quality of these studies was evaluated by using the Physiotherapy Evidence Database (PEDro) criteria. The effect of exercise was evaluated in four studies with a single bout of endurance activity, two studies with long-term endurance activity, and one study with a single bout of endurance activity as well as long-term endurance activity. The results of our systematic review provide evidence that endurance exercise might augment the peripheral BDNF concentration in post-stroke individuals.

Effect of Physical Activity on Cognitive Impairment in Patients With Cerebrovascular Diseases: A Systematic Review and Meta-Analysis

Background and Purpose

This study investigates the effect of physical activity (PA) on cognition in patients with cerebrovascular disease and explored the maximum benefit of different PA characteristics.

Methods

Databases, such as Pubmed, Web of Science, Embase, and Cochrane Library, were searched from their inception to May 31, 2021. Standardized mean difference (SMD) and 95% confidence intervals (CIs) were calculated to generate a forest plot. In addition, subgroup analysis, moderation analysis, and regression analysis were performed to explore the possible adjustment factors.

Results

In total, 22 studies that met the criteria were included, demonstrating data from 1,601 participants. The results indicated that PA produced a positive effect on the global cognition for patients with cerebrovascular disease (SMD: 0.20 [95% CI: 0.12-0.27]), at the same time, PA training prominently improved executive function (SMD: 0.09 [95% CI: 0.00-0.17]) and working memory (SMD: 0.25 [95% CI: 0.10-0.40]). Furthermore, patients with baseline cognitive impairment received the greater benefit of PA on cognition (SMD: 0.24 [95% CI: 0.14-0.34]) than those without cognitive impairment before intervention (SMD: 0.15 [95% CI: 0.04-0.26]). For patients in the acute stage (≤ 3 months), PA did not rescue impairment dysfunction significantly (SMD: 0.08 [95% CI: -0.04-0.21]) and remarkable cognitive gains were detected in the chronic stage of participants (>3 months) (SMD: 0.25 [95% CI: 0.16-0.35]). Moderate intensity PA showed a larger pooled effect size (SMD: 0.23 [95% CI: 0.11-0.36]) than low intensity (SMD: -0.01 [95% CI: -0.44-0.43]) and high intensity (SMD: 0.16 [95% CI: 0.03-0.29]). However, the different types, duration, and frequency of PA resulted in no differences in the improvement of cognitive function. Further regression analysis demonstrated that the beneficial effects of PA on cognition are negatively correlated with age (p < 0.05).

Conclusions

This study revealed that PA can prominently improve the cognitive ability in patients with cerebrovascular diseases and strengthened the evidence that PA held promise as a widely accessible and effective non-drug therapy for vascular cognitive impairment (VCI).

Intermittent fasting and cognitive performance - Targeting BDNF as potential strategy to optimise brain health

Aging is the major risk factor for neurodegenerative diseases, accelerated by excessive calorie consumption and sedentary lifestyles. Bioenergetic challenges such as intermittent fasting (IF) have shown to promote lifespan and healthspan via an adaptive stress response. Activity-dependent brain-derived neurotrophic factor (BDNF) has emerged as key regulator of cognitive performance and brain health. This review aims to investigate the pathophysiological mechanisms linking IF and cognitive function with a focus on the role of BDNF, evaluating evidence from pre-clinical and human studies. A systematic literature search was performed. 82 peer-reviewed papers were accepted, critically appraised and summarised in a narrative analysis. Aging-related loss of BDNF has been associated with reduced synaptic plasticity, memory and learning as well as increased risk of cognitive impairment and Alzheimer's disease. IF was consistently reported to upregulate BDNF and improve cognitive performance in animal models. Further research is required to assess cognitive outcomes of IF in humans.

Inter-rater reliability and agreement of 6 Minute Walk Test and 10 Meter Walk Test at comfortable walk speed in patients with acute stroke

PURPOSE

Remediation of gait problems is a key feature of neurological physiotherapy We aimed to investigate the inter-rater reliability and agreement of the Six Minute Walk Test (6MWT) and Ten Meter Walk Test (10MWT), at comfortable walking speed, in hospitalized acute ischemic stroke patients.

METHOD

Forty acute first-time patients with brain stem or hemispheric ischemic stroke aged 67.4 ± 12.5 (SD), able to walk with or without an assistive device, were tested by one of three physiotherapists. Test-retest reliability was evaluated using a one-way random effects single measures model (1,1) absolute agreement-type Interclass Correlation Coefficient (ICC). Agreement was evaluated using the Standard Error of Measurement (SEM) and Smallest Detectable Change (SDC).

RESULTS

Both tests demonstrated good reliability; ICC_1,1 0.83 (CI 95% 0.70-0.90) (6MWT) and 0.76 (CI 95% 0.59-0.87) (10MWT). The 6MWT-SEM was 27.2 m (m) and the SDC was 75.4 m. The 10MWT-SEM was 0.36 meters per second (m/s) and the SDC was 1.0 m/s.

CONCLUSION

Both tests demonstrated good inter-rater reliability, confirming their discriminative ability on a group of hospitalized first-time acute ischemic stroke patients. However, the measurement error was large for both tests, which is likely due to spontaneous neurological recovery and stress in the acute phase severely affecting the individual-level agreement estimate.

Combined treatment with exercise and α5GABAAR inhibitor promotes motor function recovery after intracerebral hemorrhage

The present study aimed to examine the synergistic effects of exercise and pharmacological inhibition of the α5 subunit-containing gamma-aminobutyric acid (GABA)_A receptors (α5GABA_AR) on motor function recovery after intracerebral hemorrhage (ICH). Wistar rats were divided into five groups (n = 8 per group): SHAM, ICH, ICH + exercise (ICH + EX), ICH + L-655,708 (ICH + L6), and ICH + L-655,708 and exercise (ICH + L6EX) groups. ICH was induced by microinjection of a collagenase solution. The ICH + EX and ICH + L6EX groups exercised on a treadmill (12 m/min for 30 min/day). L-655,708 (0.5 mg/kg), a negative allosteric modulator of α5GABA_AR, was administered intraperitoneally to the ICH + L6 and ICH + L6EX groups. Each intervention was initiated 1 week after the ICH surgery and was performed for 3 weeks, followed by tissue collection, including the motor cortex and spinal cord. At 4 weeks after ICH, significant motor recovery was found in the ICH + L6EX group compared to the ICH group. L-655,708 administration increased brain-derived neurotrophic factor (BDNF) expression in the cortex. Regarding neuroplastic changes in the spinal cord, rats in the ICH + L6EX group showed a significant increase in several neuroplastic markers: 1) BDNF, 2) growth-associated protein 43 as an axonal sprouting marker, 3) synaptophysin as a synaptic marker, and 4) Nogo-A as an axonal growth inhibitor. This study is the first to demonstrate that combined treatment with exercise and α5GABA_AR inhibitor effectively promoted motor function recovery after ICH. Regarding the underlying mechanism of post-ICH recovery with the combined treatment, the present study highlights the importance of both growth and inhibitory modification of axonal sprouting in the spinal cord.

Gait Improvement in Chronic Stroke Survivors by Using an Innovative Gait Training Machine: A Randomized Controlled Trial

Chronic stroke leads to the impairment of lower limb function and gait performance. After in-hospital rehabilitation, most individuals lack continuous gait training because of the limited number of physical therapists. This study aimed to evaluate the effects of a newly invented gait training machine (I-Walk) on lower limb function and gait performance in chronic stroke individuals. Thirty community-dwelling chronic stroke individuals were allocated to the I-Walk machine group (n = 15) or the overground gait training (control) group (n = 15). Both groups received 30 min of upper limb and hand movement and sit-to-stand training. After that, the I-Walk group received 30 min of I-Walk training, while the control followed a 30-minute overground training program. All the individuals were trained 3 days/week for 8 weeks. The primary outcome of the motor recovery of lower limb impairment was measured using the Fugl-Meyer Assessment (FMA). The secondary outcomes for gait performance were the 6-minute walk test (6 MWT), the 10-meter walk test (10 MWT), and the Timed Up and Go (TUG). The two-way mixed-model ANOVA with the Bonferroni test was used to compare means within and between groups. The post-intervention motor and sensory subscales of the FMA significantly increased compared to the baseline in both groups. Moreover, the 6 MWT and 10 MWT values also improved in both groups. In addition, the mean difference of TUG in the I-Walk was higher than the control. The efficiency of I-Walk training was comparable to overground training and might be applied for chronic stroke gait training in the community.

Cognitive and Linguistic Benefits of Aerobic Exercise: A State-of-the-Art Systematic Review of the Stroke Literature

This systematic review aimed to determine how aerobic exercise affects cognition after stroke, with particular focus on aphasia and language improvement. Methodological quality was assessed with the PEDro+ scale with half of the 27 included studies rated as high quality. Data extraction focused on cognitive effects of aerobic exercise post-stroke, intervention characteristics, outcome measures, and participant characteristics. Whereas attention, memory, and executive functioning measures were common across the included studies, no study included a language-specific, performance-based measure. Seventeen studies reported positive cognitive effects, most frequently in the domains of attention, memory and executive functioning. Variability in outcome measures, intervention characteristics, and participant characteristics made it difficult to identify similarities among studies reporting positive cognitive effects of exercise or among those studies reporting null outcomes. Only three studies provided specific information about the number of individuals with aphasia included or excluded, who comprise approximately one-third of the stroke population. The review identified patent gaps in our understanding of how aerobic exercise may affect not only the cognitive domain of language post-stroke but also the broader cognitive functioning of individuals with post-stroke aphasia. Methodological limitations of the reviewed studies also warrant further examination of the direct impact of aerobic exercise on cognition post-stroke with careful attention to the selection and reporting of population, intervention, and outcomes.

Exercise-induced neuroprotection against cerebral ischemia/reperfusion injury is mediated via alleviating inflammasome-induced pyroptosis

As a primary nonpharmacological tool, exercise training is neuroprotective after experimental ischemic stroke by relieving neuroinflammation. However, the specific mechanism of which and anti-inflammatory effect of exercise at different intensities require in-depth investigations. To explore the issue, middle cerebral artery occlusion-reperfusion (MCAO-r) in mice were utilized, with subsequent exercise training at different intensities (high-intensity interval training versus moderate-intensity continuous training, i.e. HIIT vs. MICT) during an early phase post-modeling. The neurobehavioral assessment showed that MICT improved the performance of neurological deficit scores and rotarod test earlier, while HIIT appeared to be more efficacious to meliorate locomotor impairments and aerobic fitness at the end of intervention. Both exercise regimens inhibited the expressions of NLRP3 inflammasome components (NLRP3, ASC, and Cl.caspase-1) and pyroptosis-associated proteins (GSDMD, Cl.IL-1β, and Cl.IL-18) as indicated by western blot and immunofluorescence co-staining. Multiplex assay panel revealed that both exercise regimens reduced the levels of pro-inflammatory cytokines and upregulated anti-inflammatory cytokine. Furthermore, an increased proportion of M2-like microglia and a diminished proportion of M1-like microglia in the peri-infarct zone were observed by colocalization analysis, which was jointly validated by western blot. Here, for the first time, our study demonstrated that HIIT elicited better improvements at functional and cardiovascular levels than MICT after ischemic stroke, and anti-inflammatory effect of exercise might result from suppression in inflammasome-mediated pyroptosis by shifting microglial polarization toward neuroprotective M2 phenotype.

Handgrip as a measure of muscle strength and its physiological dependence on therapeutic variables: A randomized case

Clinical and medical data findings have traditionally been more representative of male than female subjects, and when combined, have not clearly differentiated between the groups. In this study there were no research questions initially contemplated, as the data were obtained from an educational setting, where participants completed tasks as part of a pedagogical program of preparation. The nature of the post-hoc analysis renders the study as a hypothesis-generating type rather than a hypothesis-testing one. It began as a cross-sectional quantitative analysis of performance on a task to explore the relationship between hand grip and three independent physiological variables. The data collected from all subjects were randomized since the total group of participants contained a disproportionate number of females as compared to males, this being a result of a demographic predominance of female students in a program of teacher preparation. Graphical analysis with the slope taken as a measure of hand grip dependence on three independent variables, and the correlation value used as a measure of association between variables yielded discernible differences. The grip strength dependence on the hand size as well as the wrist thickness show consistently significant differences for females only, with t test of significance (p < .001), and large effect size differences based on Cohen's d values of 3.08 and 1.92, respectively. The significance of the finding that female grip strength depends the most on wrist thickness has implications for rehabilitative and therapeutic settings.

Effects of aerobic physical exercise on neuroplasticity after stroke: systematic review

BACKGROUND

Stroke is among the leading causes of death and disability worldwide. Interventions for stroke rehabilitation aim to minimize sequelae, promote individuals' independence and potentially recover functional damage. The role of aerobic exercise as a facilitator of post-stroke neuroplasticity in humans is still questionable.

OBJECTIVE

To investigate the impact of aerobic exercise on neuroplasticity in patients with stroke sequelae.

METHODS

A systematic review of randomized clinical trials and crossover studies was performed, with searches for human studies in the following databases: PUBMED, EMBASE, LILACS and PeDRO, only in English, following the PRISMA protocol. The keywords used for selecting articles were defined based on the PICO strategy.

RESULTS

This systematic review evaluated the impacts of aerobic exercise on neuroplasticity through assessment of neural networks and neuronal excitability, neurotrophic factors, or cognitive and functional assessment. Studies that evaluated the effects of aerobic exercise on neuroplasticity after stroke measured through functional resonance (fMRI) or cortical excitability have shown divergent results, but aerobic exercise potentially can modify the neural network, as measured through fMRI. Additionally, aerobic exercise combined with cognitive training improves certain cognitive domains linked to motor learning. Studies that involved analysis of neurotrophic factors to assess neuroplasticity had conflicting results.

CONCLUSIONS

Physical exercise is a therapeutic intervention in rehabilitation programs that, beyond the known benefits relating to physical conditioning, functionality, mood and cardiovascular health, may also potentiate the neuroplasticity process. Neuroplasticity responses seem more robust in moderate to high-intensity exercise training programs, but dose-response heterogeneity and non-uniform neuroplasticity assessments limit generalizability.

Neuromuscular Electric Stimulation in Addition to Exercise Therapy in Patients with Lower Extremity Paresis Due to Acute Ischemic Stroke. A proof-of-concept randomised controlled trial

INTRODUCTION

Exercise therapy and neuromuscular electrical stimulation (NMES) during the initial 14 days after stroke may benefit recovery of gait. We aimed to determine whether poststroke NMES of vastus medial and tibial muscles during exercise therapy is more effective than exercise therapy alone.

MATERIALS AND METHODS

In this proof-of-concept randomised trial patients with first-ever acute ischemic stroke and a leg paresis (40-85 years of age) were randomised (1:1) to 10 min of daily NMES + exercise therapy or exercise therapy alone. Primary outcome was the between-group difference in change in 6 min Walk Test (6MWT) at 90 days post stroke estimated with a mixed regression model. Secondary outcomes included 10 m Walk Test, Fugl-Meyer Motor Assessment, Guralnik Timed Standing Balance, Sit to Stand, Timed Up and Go, EQ-5D-5L, Montreal Cognitive Assessment and Becks Depression Inventory.

RESULTS

50 stroke survivors (25 in each group) with a mean age of 67 years (range 43-83) were included. An insignificant between-group difference in change of 28.3 m (95%CI -16.0 to 72.6, p = 0.23, adjusted for baseline) in 6MWT at 90-days follow-up was found, in favour of the NMES group. All secondary outcomes showed no statistically significant between-group difference. The conclusion was that adding NMES to exercise therapy had no effect on poststroke walking distance measured by the 6 MWT or any of the secondary outcomes.

CONCLUSIONS

In this proof-of-concept RCT, we demonstrated that NMES in addition to exercise therapy during the first 14 days after onset of ischemic stroke did not improve walking distance or any of the secondary outcomes. Future studies with a longer trial period, stratifying patients into subgroups with comparable patterns of expected spontaneous recovery - if possible within 48 h post stroke, and greater sample size, than in this study are suggestions of how rehabilitation research could go on exploring the potential for NMES as an amplifier in stroke recovery.

Effects of Aerobic Exercise on Serum Biomarkers of Neuroplasticity and Brain Repair in Stroke: A Systematic Review

OBJECTIVE

To provide a novel overview of the literature and to summarize the evidence for the effects of aerobic exercise (AE) on serum biomarkers neuroplasticity and brain repair in survivors of stroke.

DATA SOURCES

We conducted a systematic review and searched MEDLINE, Embase, and Cochrane CENTRAL using terms related to AE, neuroplasticity, brain repair, and stroke.

STUDY SELECTION

Titles, abstracts, and selected full texts were screened by 2 independent reviewers against the following inclusion criteria: including adult survivors of stroke, completing an AE intervention working within the AE capacity, and measuring at least 1 blood biomarker outcome of interest.

DATA EXTRACTION

Two independent reviewers extracted data and assessed risk of bias using Risk of Bias in Nonrandomized Studies-of Interventions and Cochrane's Risk of Bias 2 tools.

DATA SYNTHESIS

Nine studies (n=215 participants) were included, reporting on the following outcomes: brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1 (IGF-1), vascular endothelial growth factor (VEGF), cortisol, interleukin 6, and myeloperoxidase. A single bout of high-intensity interval training significantly increased BDNF, IGF-1, and VEGF levels, and a 40-45-minute, 24-session, continuous 8-week AE training program significantly increased BDNF levels. No significant difference in response to any other AE intervention was found in other serum biomarkers.

CONCLUSIONS

AE can significantly increase BDNF, IGF-1, and VEGF across different AE protocols in survivors of stroke. However, more research is needed to determine the optimal exercise intensity and modalities, specifically in survivors of acute and subacute stroke, and how this may relate to functional outcomes.

Effects of detraining on preconditioning exercise-induced neuroprotective potential after ischemic stroke in rats

Preconditioning exercise prior to stroke exerts neuroprotection, which is an endogenous strategy that leads the brain cells to express several intrinsic factors and inhibits their apoptosis. However, it is unclear how long these benefits last after exercise cessation. The aim of this study was to investigate the effects of detraining on preconditioning exercise-induced neuroprotective potential after stroke. Rats were trained using a treadmill for aerobic exercise 5 days each week for 3 weeks, and their neuroprotective effects were examined until 3 weeks after exercise cessation. Stroke was induced by 60 min of left middle cerebral artery occlusion at 3 days, 1, 2, and 3 weeks after exercise cessation. Infarct volume, neurological deficits, sensorimotor function, expression levels of brain-derived neurotrophic factor (BDNF), hypoxia-induced factor-1α (HIF-1α), glial fibrillary acidic protein (GFAP), and P2X7 receptors, and apoptosis activity were examined using immunohistochemical and western blot analyses. Preconditioning exercise significantly reduced infarct volume and ameliorated sensorimotor function after stroke, and its beneficial effects were observed until 2 weeks after exercise cessation. The expression level of BDNF in the ischemic brain was significantly upregulated at 3 days after exercise cessation; however, the expression levels of HIF-1α, GFAP, and P2X7 receptor were significantly increased until 2 weeks after exercise cessation; thereby, significant anti-apoptotic effects were lost at 3 weeks of detraining. Our findings suggest that preconditioning exercise-induced neuroprotective potential may be lost shortly after exercise cessation. Neuroprotection through intrinsic protective factors, such as BDNF and HIF-1α, may provide different neuroprotective mechanisms in a time-dependent manner during detraining.

Effects of Combined Interventions with Aerobic Physical Exercise and Cognitive Training on Cognitive Function in Stroke Patients: A Systematic Review

(1) Background: Stroke is a major cause of permanent disability in multiple functions, including the cognitive domain. Since both cognitive training and aerobic physical exercise may exert positive effects on cognition after stroke, one may expect synergistic benefits when combining both interventions. (2) Methods: We carried out a systematic search of studies testing, in adult stroke patients, whether structured aerobic exercise combined with cognitive training led to higher cognitive benefits than either of these interventions when applied singly, or than interventions not including aerobic exercise or cognitive training. (3) Results: Five fair-quality randomized controlled trials fulfilled the search criteria. Exercise intensity was moderate-vigorous and cognitive training was mainly computer-based. The studies were heterogeneous regarding the cognitive tests used, and for this reason, a meta-analysis was not performed. Only three studies included follow-up assessment. The combined intervention was associated with pre-post improvement in at least one cognitive test in all the studies, and with higher positive effects compared to other conditions (although statistical significance was not always reached) in four studies. (4) Conclusions: Further trials including a long-term follow-up and comprehensive neuropsychological testing should be undertaken to determine whether combined aerobic exercise and cognitive training leads to additive cognitive benefits after stroke.

Fitness Shifts the Balance of BDNF and IL-6 from Inflammation to Repair among People with Progressive Multiple Sclerosis

Physical sedentarism is linked to elevated levels of circulating cytokines, whereas exercise upregulates growth-promoting proteins such as brain-derived neurotrophic factor (BDNF). The shift towards a 'repair' phenotype could protect against neurodegeneration, especially in diseases such as multiple sclerosis (MS). We investigated whether having higher fitness or participating in an acute bout of maximal exercise would shift the balance of BDNF and interleukin-6 (IL-6) in serum samples of people with progressive MS (n = 14), compared to matched controls (n = 8). Participants performed a maximal graded exercise test on a recumbent stepper, and blood samples were collected at rest and after the test. We assessed walking speed, fatigue, and maximal oxygen consumption (V·O2max). People with MS achieved about 50% lower V·O2max (p = 0.003) than controls. At rest, there were no differences in BDNF between MS and controls; however, IL-6 was significantly higher in MS. Higher V·O2max was associated with a shift in BDNF/IL-6 ratio from inflammation to repair (R = 0.7, p = 0.001) when considering both groups together. In the MS group, greater ability to upregulate BDNF was associated with faster walking speed and lower vitality. We present evidence that higher fitness indicates a shift in the balance of blood biomarkers towards a repair phenotype in progressive MS.

Probing the Brain-Body Connection Using Transcranial Magnetic Stimulation (TMS): Validating a Promising Tool to Provide Biomarkers of Neuroplasticity and Central Nervous System Function

Transcranial magnetic stimulation (TMS) is a non-invasive method used to investigate neurophysiological integrity of the human neuromotor system. We describe in detail, the methodology of a single pulse TMS protocol that was performed in a large cohort of people (n = 110) with multiple sclerosis (MS). The aim was to establish and validate a core-set of TMS variables that predicted typical MS clinical outcomes: walking speed, hand dexterity, fatigue, and cognitive processing speed. We provide a brief and simple methodological pipeline to examine excitatory and inhibitory corticospinal mechanisms in MS that map to clinical status. Delayed and longer ipsilateral silent period (a measure of transcallosal inhibition; the influence of one brain hemisphere's activity over the other), longer cortical silent period (suggestive of greater corticospinal inhibition via GABA) and higher resting motor threshold (lower corticospinal excitability) most strongly related to clinical outcomes, especially when measured in the hemisphere corresponding to the weaker hand. Greater interhemispheric asymmetry (imbalance between hemispheres) correlated with poorer performance in the greatest number of clinical outcomes. We also show, not surprisingly, that TMS variables related more strongly to motor outcomes than non-motor outcomes. As it was validated in a large sample of patients with varying severities of central nervous system dysfunction, the protocol described herein can be used by investigators and clinicians alike to investigate the role of TMS as a biomarker in MS and other central nervous system disorders.

Is High-Intensity Interval Training Suitable to Promote Neuroplasticity and Cognitive Functions after Stroke?

Stroke-induced cognitive impairments affect the long-term quality of life. High-intensity interval training (HIIT) is now considered a promising strategy to enhance cognitive functions. This review is designed to examine the role of HIIT in promoting neuroplasticity processes and/or cognitive functions after stroke. The various methodological limitations related to the clinical relevance of studies on the exercise recommendations in individuals with stroke are first discussed. Then, the relevance of HIIT in improving neurotrophic factors expression, neurogenesis and synaptic plasticity is debated in both stroke and healthy individuals (humans and rodents). Moreover, HIIT may have a preventive role on stroke severity, as found in rodents. The potential role of HIIT in stroke rehabilitation is reinforced by findings showing its powerful neurogenic effect that might potentiate cognitive benefits induced by cognitive tasks. In addition, the clinical role of neuroplasticity observed in each hemisphere needs to be clarified by coupling more frequently to cellular/molecular measurements and behavioral testing.

Bioethical, Reproducibility, and Translational Challenges of Animal Models

There is no prescribed stage or standardized point at which an animal model protocol is reviewed for reproducibility and translatability. The method of review for a reproducible and translatable study is not consistently documented in peer literature, and this is a major challenge for those working with animal models of human diseases. If the study is ill designed, it is impossible to perform an accurate harm/benefit analysis. In addition, there may be an ethical challenge if the work is not reproducible and translatable. Animal welfare regulations and other documents of control clearly state the role of the Institutional Animal Care and Use Committees are to look at science justification within the context of animal welfare. This article, concentrating on models not governed by regulations, outlines issues and offers recommendations for refining animal model review with a goal to improve study reproducibility and translatability.

Accuracy of wrist-worn heart rate monitors during physical therapy sessions among hemiparetic inpatients with stroke

[Purpose] We aimed to examine the accuracy of heart rate monitors worn on the wrist by patients with stroke. The wrist worn heart rate monitor could improve the quality of rehabilitation by monitoring exercise intensity during physical therapy. [Participants and Methods] Thirty inpatients with subacute hemiparetic stroke wore heart rate monitors on both (non-paretic and paretic) wrists, as well as a chest heart rate monitor. We recorded the heart rate values measured at the wrist and chest every minute during physical therapy sessions. The wrist monitors were an optical heart rate measurement device based on photoplethysmography, and the chest monitor was a traditional chest device based on electrocardiography. The relative and absolute reliabilities between the heart rate measurements from the wrist and chest monitors were calculated. [Results] The intraclass correlation coefficients for model 2.1 ranged from 0.75 to 0.79. Bland-Altman analysis revealed a very slight fixed bias; however, no significant proportional bias was observed. For the non-paretic and paretic sides, the lower and upper limits of agreement ranged from −21.8 to 23.8 beats/min and from −20.8 to 21.6 beats/min, and the mean absolute percentage errors were 6.7% and 5.9%, respectively. The Cohen’s d value was small. [Conclusion] The relative reliability of the wrist heart rate monitors was substantial. The absolute reliability as bias in wrist heart rate and chest heart rate was small, but heart rates estimated from wrist monitors were not particularly accurate.

Mini Review (Part I): An Experimental Concept on Exercise and Ischemic Conditioning in Stroke Rehabilitation

Stroke remains a leading cause of adult death and disability. Poststroke rehabilitation is vital for reducing the long-term sequelae of brain ischemia. Recently, physical exercise training has been well established as an effective rehabilitation tool, but its efficacy depends on exercise parameters and the patient's capacities, which are often altered following a major cerebrovascular event. Thus, ischemic conditioning as a rehabilitation intervention was considered an “exercise equivalent,” but the investigation is still in its relative infancy. In this mini-review, we discuss the potential for physical exercise or ischemic conditioning and its relation to angiogenesis, neurogenesis, and plasticity in stroke rehabilitation. This allows the readers to understand the context of the research and the application of ischemic conditioning in poststroke rehabilitation.

Role of Regular Physical Activity in Neuroprotection against Acute Ischemia

One of the major obstacles that prevents an effective therapeutic intervention against ischemic stroke is the lack of neuroprotective agents able to reduce neuronal damage; this results in frequent evolution towards a long-term disability with limited alternatives available to aid in recovery. Nevertheless, various treatment options have shown clinical efficacy. Neurotrophins such as brain-derived neurotrophic factor (BDNF), widely produced throughout the brain, but also in distant tissues such as the muscle, have demonstrated regenerative properties with the potential to restore damaged neural tissue. Neurotrophins play a significant role in both protection and recovery of function following neurological diseases such as ischemic stroke or traumatic brain injury. Unfortunately, the efficacy of exogenous administration of these neurotrophins is limited by rapid degradation with subsequent poor half-life and a lack of blood-brain-barrier permeability. Regular exercise seems to be a therapeutic approach able to induce the activation of several pathways related to the neurotrophins release. Exercise, furthermore, reduces the infarct volume in the ischemic brain and ameliorates motor function in animal models increasing astrocyte proliferation, inducing angiogenesis and reducing neuronal apoptosis and oxidative stress. One of the most critical issues is to identify the relationship between neurotrophins and myokines, newly discovered skeletal muscle-derived factors released during and after exercise able to exert several biological functions. Various myokines (e.g., Insulin-Like Growth Factor 1, Irisin) have recently shown their ability to protects against neuronal injury in cerebral ischemia models, suggesting that these substances may influence the degree of neuronal damage in part via inhibiting inflammatory signaling pathways. The aim of this narrative review is to examine the main experimental data available to date on the neuroprotective and anti-ischemic role of regular exercise, analyzing also the possible role played by neurotrophins and myokines.

Determining Maximal Tolerable Aerobic Training Intensity in the Acute Phase after Stroke: a Novel Dose Ranging Trial Protocol

INTRODUCTION

There is strong evidence that cardiorespiratory fitness (CRF) training improves fitness and mobility after stroke. Despite the large number of studies, the most efficacious dose is yet to be determined. Furthermore, the safety of early post-stroke training, while theoretically beneficial, remains uncertain. The aim of this study is to determine the maximum safe and tolerable intensity of CRF training early post-stroke.

METHODS

This is a stratified (low to moderate exercise capacity), Phase I, 5+5 dose ranging trial protocol. Participants will be recruited within one month post-stroke and stratified by their exercise-capacity (i.e. low and moderate capacity). Cohorts of five participants will perform 12 interval-based training sessions for four-weeks at a pre-determined target-intensity. The intensity will increase in each consecutive cohort, in each stratum according to pre-defined rules until the maximum safe and tolerable intensity is reached, as determined by the occurrence of dose-limiting events and occurrence of adverse events. Dose-limiting events are defined as symptoms indicative of over-training including pain and inability to perform usual activities.

STUDY OUTCOME

Maximum safe and tolerable intensity of CRF training in stroke survivors with low and moderate exercise capacity.

DISCUSSION

This study is a first step in the systematic development of a CRF training intervention. We believe similar dose ranging designs may be useful for development of other rehabilitation interventions in different study populations.

Aerobic exercise attenuates neurodegeneration and promotes functional recovery - Why it matters for neurorehabilitation & neural repair

Aerobic exercise facilitates optimal neurological function and exerts beneficial effects in neurologic injuries. Both animal and clinical studies have shown that aerobic exercise reduces brain lesion volume and improves multiple aspects of cognition and motor function after stroke. Studies using animal models have proposed a wide range of potential molecular mechanisms that underlie the neurological benefits of aerobic exercise. Furthermore, additional exercise parameters, including time of initiation, exercise dosage (exercise duration and intensity), and treatment modality are also critical for clinical application, as identifying the optimal combination of parameters will afford patients with maximal functional gains. To clarify these issues, the current review summarizes the known neurological benefits of aerobic exercise under both physiological and pathological conditions and then considers the molecular mechanisms underlying these benefits in the contexts of stroke-like focal cerebral ischemia and cardiac arrest-induced global cerebral ischemia. In addition, we explore the key roles of exercise parameters on the extent of aerobic exercise-induced neurological benefits to elucidate the optimal combination for aerobic exercise intervention. Finally, the current challenges for aerobic exercise implementation after stroke are discussed.

Multiple doses of cell therapy and neurorehabilitation in amyotrophic lateral sclerosis: A case report

Cell therapy, along with intensive rehabilitation has been shown to significantly improve outcomes in amyotrophic lateral sclerosis (ALS), in addition to standard therapy. We present a 40-years-old male ALS patient, suffering for the past four years, who underwent multiple doses of cell therapy at our institution. Along with riluzole treatment and lithium co-administration, his treatment involved multiple intrathecal transplants of autologous bone marrow-derived mononuclear cells, followed by multidisciplinary neurorehabilitation. The outcome measures of ALSFunctional Rating Scale Revised score remained stable, and importantly, Six Minute Walk Test distance improved from 475.2 m to 580.8 m, over a span of 16 months. Improved outcomes are indicative of slowing down of disease progression. Multiple doses of intrathecal autologous cell therapy along with rehabilitation and lithium, in addition to standard riluzole treatment is a novel approach for decelerating disease progression and qualitatively improving living conditions for ALS patients and their caregivers.

An Extra Breath of Fresh Air: Hyperbaric Oxygenation as a Stroke Therapeutic

Stroke serves as a life-threatening disease and continues to face many challenges in the development of safe and effective therapeutic options. The use of hyperbaric oxygen therapy (HBOT) demonstrates pre-clinical effectiveness for the treatment of acute ischemic stroke and reports reductions in oxidative stress, inflammation, and neural apoptosis. These pathophysiological benefits contribute to improved functional recovery. Current pre-clinical and clinical studies are testing the applications of HBOT for stroke neuroprotection, including its use as a preconditioning regimen. Mild oxidative stress may be able to prime the brain to tolerate full extensive oxidative stress that occurs during a stroke, and HBOT preconditioning has displayed efficacy in establishing such ischemic tolerance. In this review, evidence on the use of HBOT following an ischemic stroke is examined, and the potential for HBOT preconditioning as a neuroprotective strategy. Additionally, HBOT as a stem cell preconditioning is also discussed as a promising strategy, thus maximizing the use of HBOT for ischemic stroke.

Structural and Functional Remodeling of the Brain Vasculature Following Stroke

Maintenance of cerebral blood vessel integrity and regulation of cerebral blood flow ensure proper brain function. The adult human brain represents only a small portion of the body mass, yet about a quarter of the cardiac output is dedicated to energy consumption by brain cells at rest. Due to a low capacity to store energy, brain health is heavily reliant on a steady supply of oxygen and nutrients from the bloodstream, and is thus particularly vulnerable to stroke. Stroke is a leading cause of disability and mortality worldwide. By transiently or permanently limiting tissue perfusion, stroke alters vascular integrity and function, compromising brain homeostasis and leading to widespread consequences from early-onset motor deficits to long-term cognitive decline. While numerous lines of investigation have been undertaken to develop new pharmacological therapies for stroke, only few advances have been made and most clinical trials have failed. Overall, our understanding of the acute and chronic vascular responses to stroke is insufficient, yet a better comprehension of cerebrovascular remodeling following stroke is an essential prerequisite for developing novel therapeutic options. In this review, we present a comprehensive update on post-stroke cerebrovascular remodeling, an important and growing field in neuroscience, by discussing cellular and molecular mechanisms involved, sex differences, limitations of preclinical research design and future directions.

Hyperbaric oxygen and focused rehabilitation program: a feasibility study in improving upper limb motor function after stroke

Neuroplasticity and recovery after stroke can be enhanced by a rehabilitation program pertinent to upper limb motor function exercise and mental imagery (EMI) as well as hyperbaric oxygen therapy (HBOT). We assessed feasibility and safety of the combined approach utilizing both HBOT and EMI, and to derive preliminary estimates of its efficacy. In this randomized controlled trial, 27 patients with upper extremity hemiparesis at 3-48 months after stroke were randomized to receive either a complementary rehabilitation program of HBOT-EMI (intervention group), or EMI alone (control group). Feasibility and safety were assessed as total session attendance, duration of sessions, attrition rates, missing data, and intervention-related adverse events. Secondary clinical outcomes were assessed with both objective tools and self-reported measures at baseline, 8 weeks (end of treatment), and 12-weeks follow-up. Session attendance, duration, and attrition rate did not differ between the groups; there were no serious adverse events. Compared with baseline, there were significant sustained improvements of objective and subjective outcomes' measures in the intervention group, and a single improvement in an objective measure in the control group. Between-group outcome comparisons were not statistically significant. This study demonstrated that the combination HBOT-EMI was a safe and feasible approach in patients recovering from chronic stroke. There were also trends for improved motor function of the affected upper limb after the treatments. ClinicalTrials.gov registration no.: NCT02666469. Novelty HBOT combined with an upper limb exercise and mental imagery rehabilitation program is feasible and safe in chronic stroke patients. This combined approach showed trends for improved functional recovery.

Walking Training Enhances Corticospinal Excitability in Progressive Multiple Sclerosis-A Pilot Study

Background: Inflammatory lesions and neurodegeneration lead to motor, cognitive, and sensory impairments in people with multiple sclerosis (MS). Accumulation of disability is at least partially due to diminished capacity for neuroplasticity within the central nervous system. Aerobic exercise is a potentially important intervention to enhance neuroplasticity since it causes upregulation of neurotrophins and enhances corticospinal excitability, which can be probed using single-pulse transcranial magnetic stimulation (TMS). Whether people with progressive MS who have accumulated substantial disability could benefit from walking rehabilitative training to enhance neuroplasticity is not known.

Objective: We aimed to determine whether 10 weeks of task-specific walking training would affect corticospinal excitability over time (pre, post, and 3-month follow-up) among people with progressive MS who required walking aids.

Results: Eight people with progressive MS (seven female; 29–74 years old) with an Expanded Disability Status Scale of 6–6.5 underwent harness-supported treadmill walking training in a temperature controlled room at 16°C (10 weeks; three times/week; 40 min at 40–65% heart rate reserve). After training, there was significantly higher corticospinal excitability in both brain hemispheres, reductions in TMS active motor thresholds, and increases in motor-evoked potential amplitudes and slope of the recruitment curve (REC). Decreased intracortical inhibition (shorter cortical silent period) after training was noted in the hemisphere corresponding to the stronger hand only. These effects were not sustained at follow-up. There was a significant relationship between increases in corticospinal excitability (REC, area under the curve) in the hemisphere corresponding to the stronger hand and lessening of both intensity and impact of fatigue on activities of daily living (Fatigue Severity Scale and Modified Fatigue Impact Scale, respectively).

Conclusion: Our pilot results support that vigorous treadmill training can potentially improve neuroplastic potential and mitigate symptoms of the disease even among people who have accumulated substantial disability due to MS.

Pharmacological Interventions and Rehabilitation Approach for Enhancing Brain Self-repair and Stroke Recovery

Neuroplasticity is a natural process occurring in the brain for the entire life. Stroke is the leading cause of long term disability and a huge medical and financial problem throughout the world. Research conducted over the past decade focused mainly on neuroprotection in the acute phase of stroke while very little studies target the chronic stage. Recovery after stroke depends on the ability of our brain to reestablish the structural and functional organization of neurovascular networks. Combining adjuvant therapies and drugs may enhance the repair processes and restore impaired brain functions. Currently, there are some drugs and rehabilitative strategies that can facilitate brain repair and improve clinical effect even years after stroke onset. Moreover, some of the compounds such as citicoline, fluoxetine, niacin, levodopa, etc. are already in clinical use or are being trialed in clinical issues. Many studies are also testing cell therapies; in our review, we focused on studies where cells have been implemented at the early stage of stroke. Next, we discuss pharmaceutical interventions. In this section, we selected methods of cognitive, behavioral, and physical rehabilitation as well as adjuvant interventions for neuroprotection including noninvasive brain stimulation and extremely low-frequency electromagnetic field. The modern rehabilitation represents a new model of physical interventions with the limited therapeutic window up to six months after stroke. However, previous studies suggest that the time window for stroke recovery is much longer than previously thought. This review attempts to present the progress in neuroprotective strategies, both pharmacological and non-pharmacological that can stimulate the endogenous neuroplasticity in post-stroke patients.